In FIGS. 1A to 1C, there is shown conventional double needles for injecting liquid medicine in which there is provided a set of double needles composed of an inner needle 1 and an outer needle 2 respectively having bevels 1a and 2a and being fixed to bases 3 and 4. FIG.1A shows the construction of a set of double needles in which the inner needle 1 is combined to be inserted into the outer needle 2, while FIGS. 1B and 1C show the inner and outer needles 1 and 2 which are separated from one another.
According to the conventional set of double needles for injecting liquid medicine, the double needles are punctured into a human body to reach the affected part thereof in the construction as shown in FIG. 1A whereafter liquid medicine is injected into the affected part through the inner needle 1 to the base 3 of which a syringe (not shown) containing the liquid medicine is connected. On the other hand, a large amount of liquid medicine is injected in a short period where a syringe (not shown) containing that amount of the liquid medicine is connected to the base 4 of the outer needle 4 from which the inner needle 1 is removed as shown in FIG. 1B.
In the conventional set of double needles for injecting liquid medicine, however, pain is increased for a patient because more than a single puncturing is needed where liquid medicine is injected into a plurality of the affected parts in a predetermined area and where the affected part to be injected is different.